Little dwarf galaxy, big black hole

This illustration shows the supermassive black hole in the middle of the very dense galaxy M60-UCD1, weighing as much as 21 million suns.

This illustration shows the supermassive black hole in the middle of the very dense galaxy M60-UCD1, weighing as much as 21 million suns. (NASA, ESA, D. Coe, G. Bacon (Space Telescope Science Institute))

This image shows the massive elliptical galaxy Messier 60, 120 million light-years across and containing 400 billion stars. The inset shows the dwarf galaxy M60-UDC1, 300 light-years across; it may be the remnant of a larger galaxy torn apart during a close encounter with Messier 60.

This image shows the massive elliptical galaxy Messier 60, 120 million light-years across and containing 400 billion stars. The inset shows the dwarf galaxy M60-UDC1, 300 light-years across; it may be the remnant of a larger galaxy torn apart during a close encounter with Messier 60. (NASA, ESA and A. Seth (University of Utah))